Recording Details

Abstract

In the low energy re¬gime, precision measurements of spin precession have gained increased attention as an alternative pathway to physics beyond the standard model. These measurements aim at the detection of minute frequency changes superimposed on low Larmor frequencies at extremely weak magnetic fields. Such measurements require an effective shielding against the magnetic field of the Earth and other perturbations. For measuring the precession frequency with high precision, a long lifetime of the precessing nuclear magnetization is required, thus the homogeneity of the applied field is a crucial parameter. In addition, criteria are needed that unambiguously distinguish magnetic artifacts from the non-magnetic exotic interactions that we search for. This can be accomplished by the concept of co-magnetometry, i.e., by simultaneous measuring the precession of two nuclear species such as 3He and 129Xe. Yet another kind of co-magnetometry is the use of SQUIDs for monitoring the spin precession. SQUIDs are magnetic field detectors of their own kind, which can measure the oscillating magnetic field generated by the precessing nuclear magnetic moment as well as the magnetic dc background field. In this presentation, I will report on the current state of the art in our lab in measurements of nuclear spin precession of noble gases.